Networks, such as the Internet, have become an increasingly important part of our everyday lives. Millions of people now access the Internet on a daily basis to shop for goods and services and obtain information of interest.
For example, suppose an individual wishes to purchase a printer via the Internet. The individual accesses the Internet and types in a vendor's uniform resource locator (URL). The individual may then access that vendor's home page to determine whether the vendor has the product that this individual wishes to purchase.
If the individual does not know which vendors sell printers, the individual may access a web site associated with a search engine. The individual enters the generic term “printer” into the search engine to attempt to locate a vendor that sells printers. Using a search engine in this manner to locate individual web sites that offer the desired product or service often results in a list of hundreds or even thousands of “hits,” where each hit may correspond to a web page that relates to the search term.
In addition, the search engine may provide companies' advertisements relating to the product or service to which the individual is interested. For the example above, the search engine may provide advertisements for printers. The search engine may charge companies a predetermined fee each time the companies' advertisements are displayed to a user of the search engine. A more recent trend is to charge companies a fee each time their advertisement is selected by a user (i.e., each time a user clicks on the displayed advertisement).
Advertisers, however, are aware that not all clicks on their advertisements result in desired user actions or “conversions.” A conversion may be defined by the advertiser and may represent, for example, a purchase, a registration, a page-view, etc. Advertisers, therefore, like to know the conversion rate associated with their advertisements being displayed to users. This allows the advertiser to maximize their return on investment (ROI) by reducing fees paid on non-profitable advertisements.